Sensitive chemiluminescence assay for risperidone in pharmaceutical preparations

Stability indicating HPLC determination of risperidone in bulk drug and pharmaceutical formulations

The objective of the current study was to develop a validated stability-indicating assay method (SIAM) for risperidone after subjecting it to forced decomposition under hydrolysis, oxidation, photolysis, and thermal stress conditions. The liquid chromatographic separation was achieved isocratically on a symmetry C18 column (5 μm size, 250 mm × 4.6 mm i.d.) using a mobile phase containing methanol: acetonitrile (80 : 20, v/v) at a flow rate of 1 mL/min and UV detection at 280 nm. Retention time of risperidone was found to be 3.35 ± 0.01. The method was linear over the concentration range of 10-60 μg/mL(r(2) = 0.998) with a limit of detection and quantitation of 1.79 and 5.44 μg/mL, respectively. The method has the requisite accuracy, specificity, sensitivity, and precision to assay risperidone in bulk form and pharmaceutical dosage forms. Degradation products resulting from the stress studies did not interfere with the detection of Risperidone, and the assay is thus stability indicating.

Recent applications of flow-injection and sequential-injection analysis techniques to chemiluminescence determination of pharmaceuticals

A review is presented on the state of the art of the chemiluminescence analysis of pharmaceuticals by the two most relevant automated controlled-flow methodologies--flow-injection analysis (FIA) and sequential-injection analysis (SIA). The current chemiluminometric applications of FIA and SIA in pharmaceutical analysis are discussed with special emphasis on the analytical figures of merit and sample matrix characteristics. The review involving 211 references and covering papers published between 2001 and 2006 is divided into several sections according to the fundamental types of chemiluminescence systems employed.

Rapid determination of clindamycin in medicine with myoglobin–luminol chemiluminescence system

A sensitive chemiluminescence method, based on the inhibitory effect of clindamycin on the chemiluminescence reaction between luminol and myoglobin in a flow-injection system, is proposed for the determination of clindamycin. The decrement of chemiluminescence intensity is linear with the logarithm of clindamycin concentration over the range from 0.1 to 70.0 ng ml-1 (r2=0.9995), with the detection limit of 0.03 ng ml-1 (3sigma). At a flow rate of 2.0 ml min-1, a complete analytical process could be performed within 0.5 min, including sampling and washing, with a relative standard deviation of less than 3.0% (n=5). The proposed procedure was applied successfully to the determination of clindamycin in capsules without any pretreatment process.